Means for securing inverted t-shaped members in a metal grid



Apnl 15, 1958 s. GRIFFITH 2,830,683

MEANS FOR SECURING INVERTED T-SHAPED MEMBERS IN A METAL GRID Filed Feb.23, 1954 2 Sheets-Sheet 1 I E I] l nvwszvron H I 'STEWARD GRIFFITHATTORNEY April 15, 1953 s GRIFFITH 2,830,683

MEANS FOR SECURIN G INVERTED T-SHAPED MEMBERS IN A METAL GRID Filed Feb.23, 1954 2 Sheets-Sheet 2 25 24 26 I is ii 5 l8 1 l3 fi3 fi l7 :22 v 6l2 l2 6 l4 l3 fi INVENTOR. STEWARD GRIFFITH ATTORNEY 2,830,683 PatentedApr. 15, 1958 I ice MEANS FOR SECURING INVERTED T-SHAPED MEMBERS m AMETAL GRID Steward Grifi'ith, Portland, Greg.

Application February 23, 1954, Serial No. 411,873

2 Claims. (Cl. 189-36) This invention relates in general to the formingof metal grids or grill Work in which substantially T-shaped metalmembers are arranged in relative crosswise position, producing series ofintersecting joints between such members, similar to the so-calledmuntins and muntin joints.

More particularly and specifically, this invention relates to metalgrids of the type used for mounting or supporting acoustical tiles inceiling construction wherein the tilesupporting grid comprises parallelmain members and parallel transverse members, the transverse members be-1 ing supported by and extending between the main members. In suchconstruction customarily both the main and transverse members are ofidentical cross sections and constitute T-bars arranged with theirflanges forming the bottom of the structure or grid, so that theacoustical tiles, when set in place, will rest on and be supported bythe horizontal flanges of the grid members.

In a proper ceiling construction or grid of this type the bottom orhorizontal flanges of the main and transverse members should not onlyextend in the same horizontal bottom plane, and thus be flush at alljoint connections, but the joint connections should also be tight sothat there will be no gaps showing between the ends and the side edgesof the flanges of the intersecting members since such gaps are unsightlyand mar the appearance of the grid as viewed from below and thus detractfrom the overall effect of the finished ceiling structure.

Various methods and means have heretofore been devised for forming thejoints between intersecting members in such grid structures. In general,I have foundthat these either require much time and labor and thusinvolve considerable expense, or else the joints produced are faulty ineither strength or appearance.

A J principal object of the present invention is to provide improvedmeans for securing transverse, inverted T-shaped members together attheir intersections with corresponding main members in a metal grid,which will enable the grid structure to be strong, durable andsatisfactory in appearance, but which will also be practical and willnot require excessive time, labor or skill.

Another object of the invention is to provide an irnproved jointassembly for intersecting T-shaped bars in a grid construction in whichthe various parts of the assembly can be largely pre-formed so that thecompleting of the joint assembly on the job will be facilitated.

A particular object of the invention is to provide an improved jointconstruction of the type indicated in which the setting of the membersin place and the securing of these together will not require any specialskill on the part of the operator, and whereby a completely satisfactoryjoint will not fail to result with the exercise of ordinary care on thepart of the operator.

A further object of the invention is to provide a novel and improvedprefabricated joint construction for metal grids of the type indicatedin which prefabricating and preforming of the members and parts of suchconstruction can be done easily and inexpensively.

An additional object is to provide a grid construction wherein thesecuring of the transverse members together at their intersections withthe main members can be done with the aid of only a simple tool and in asatisfactory and fool-proof manner.

The manner in which and the means by which I attain these objects andincidental advantages through my invention will be readily understoodfrom the following brief description with reference to the accompanyingdrawings:

In the drawings:

Figure 1 is a fragmentary perspective view of a portion of an acousticaltile-supporting grid for a ceiling formed in accordance with myinvention, the view being taken from above the grid structure;

Figure 2 is a fragmentary sectional elevation on line 22 of Figure 1,drawn to a slightly larger scale;

Figure 3 is an elevation of one of the prefabricated transverse membersof the grid shown by itself before being mounted in place;

Figure 4 is an elevation of one of the prefabricated clips by means ofwhich the ends of a pair of aligned transverse members are securedtogether in place on a main member of the grid structure;

Figure 5 is a fragmentary sectional elevation similar to Figure 2,showing a pair of aligned transverse members and their connecting clipset-up preparatory to the securing of the same together in the gridstructure;

Figure 6 is a fragmentary plan section taken on line 66 of Figure 5;

Figure 7 is a fragmentary plan section similar to Figure 6, but showingthe clip firmly secured to one of the pair of transverse members, as theresult of a further step in the carrying out of my invention; and

Figure 8 is a fragmentary plan section taken on line 8-8 of Figure 2,showing the pair of aligned transverse members and their connecting clipsecured tightly together in position as a result of the completion ofthe final step in the mounting of the two transverse members in place.

Referring first to Figures 1 and 2, the metal grid for supporting theacoustical ceiling tiles 10 includes main T-shaped members 11, whichextend across the top of the room from one wall to the other and whichare parallel and equally spaced apart. One of such main members is shownin the portion of the grill structure illustrated in Figure 1. Short,transversely-extending T-shaped members 12 extend between the mainmembers 11 and are positioned at right angles thereto. The main members11 and the transverse members 12 are preferably identical in crosssection. The horizontal flanges 13 of the main members 11 and thehorizontal flanges 14 of the transverse members 12 extend in the samehorizontal plane,-

and the acoustical tiles 10 rest on these bottom flanges in theindividual rectangular spaces provided by the grid structure, sucharrangement being well known for ceiling constructions of this type. Themanner in which the grid structure, that is to say the main members 11and transverse members 12, are attached at their ends to the upperportion of the side walls of the room will be explained later on.

The main members 11, in addition to being precut in the proper length,are notched at regular predetermined intervals along their top edge, asshown at 15 in Figure 1, the spacing of the notches being made tocorrespond to the desired spacing of the transverse members in the gridto be constructed and thus corresponding approximately to one lateraldimension of the acoustical tiles 10, while the spacing between the mainmembers 11 will correspond approximately to the other lateral dimensionof the acoustical tiles.

In making grid structures of this type, it is necessary not only thatthe transverse members 12 be firmly Supported by the main members 11 atthe proper locations or intersections, but also that the bottom flangesof the adjoining members be absolutely flush and be held tightlytogether, so that no irregularities and no openings in the joints willbe apparent in the ceiling grid structure who viewed from below.

In the carrying out of my invention, the transverse members 12 are cutthe desired length, such length being equal to the spacing between themain members 11, or, more exactly, to the spacing between the edges ofthe flanges of successive main members. In addition to being cut in suchpredetermined length, the transverse members 12, in the carrying out ofmy invention, are each formed with a pair of spaced,longitudinally-aligned rectangular tongues 16 at one end, the tonguesbeing located at predetermined distances in from such end (see ure 3).These tongues extend in the same direction and extend towards theadjacent end of the transverse member, and the tongues are slightlyoffset so as to extend in a plane parallel to the plane of the centerrib of the transverse member. The shape, formation and relative locationof these tongues 16 will be noted upon referring to Figures 3 and 6.

For connecting each successive pair of aligned transverse members Iemploy a special saddle-shaped or U-shaped clip 17, which constitutes animportant part of my invention. The clips 17 are all identical, and, asevident, are so formed as to be slipped over the ends of the center ribsof each successive pair of aligned trans verse members 12, the clip thenextending over and resting upon the interposed main member 11. Each clip17 is notched at the center, as shown at 13 in Figure 4. The Width ofthe notch 18 is made greater than the thickness of the center rib of themain members 11 for a reason to be presently explained, and the notch 18is cut to exactly the right depth in conjunction with the deplh of thenotches 15 in the main members 11, so that when the clip is set on amain member 11, with its notch 18 resting in a notch 15' of a mainmember, the inside surface of the top or saddle of the clip will beexactly even with the top edge of the center rib of the supporting mainmember. Each clip 17 is formed with pairs of cut-out openings 19 in itsside walls. These cut-out openings 19 are located near one end of theclip and are so positioned as to register with the pair of tongues 16when that por tion of the clip is slid down into position on that end ofa transverse member in which the tongues are located.

When the clip has been set on the tongued end of one transverse memberand is positioned at the desired location on the main member 11, withthe notch 18 of the clip resting in a notch 15 of the main member, thenthe opposite end of a second transverse member 12 is slid into place inthe opposite end of the clip 17, as illustrated in Figure 5, and the twoaligned transverse members are brought into engagement respectively withthe adjacent edges of the flanges 13 of the interposed main member. Whenthe two transverse members 12, 12 and their connecting clip 17 have beencorrectly positioned with respect to the main member 11 (as illustratedin Figure 5), the clip 17 is rigidly secured to the second transversemember (thus, the transverse member on the right, as viewed in Figure5), by partially punching out two series of opposed tongue-likeindentations 25B, 2 1 (Fig. 7) through the side walls of the clip andthe interposed rib of the second transverse member. The partial punchingout of these two series of opposed, or oppositely arranged tongue-likeindentations can be easily done with a simple punch-out press of wellknown construction, and this operation results in rigidly locking theclip and the end of the second transverse member together. Other meanscould, of course, be employed for accomplishing the same purpose, as,for example, providing holes through the clip and the center rib of thesecond transverse member and then securing the clip and transversemember together by rivets or bolts. However, the punch ing out of thetwo series of locking indentations or tongues in the manner described issimpler, quicker and cheaper, and consequently I prefer this means ofsecuring the clip to the second transverse member in the carrying out ofmy method.

When the clip 17 has been rigidly secured to the second transversemember 12, the final step in the completion of the joint connectionconsists in thrusting the two tongues 16, 16 into further ofisetposition by pressing these tongues out through the receiving openings 19in the clip 17. This is also done very easily and quickly with a simplepunch-out tool.

It will be noted, by comparing Figures 7 and 8, that the forciblethrusting of the tongues 16, 16 into this further offset position notonly locks the first transverse member and the clip 17 together but alsoexerts a force to cause the first transverse member and the clip to moverelatively slightly in opposite directions, as indicated by the arrowsin Figure 8.

Since the clip 17 has previously been rigidly connected to the secondtransverse member any such relative movement between the clip and thefirst transverse member in opposite directions would producecorresponding movement of the two transverse members towards each otherand thus into tighter pressing engagement with the respective flangeedges of the intervening main member 11.

The manner in which this force is set up, tending to pull the twotransverse members against the main member, will be understood from. acomparison of Figures 7 and 8. It is due to the fact that as the extentto which the tongues 16, 16 are offset is increased the attachingportion 16A of each tongue is made to assume more nearly a right angleposition with respect to the side wall of the clip, and in this manneris thrust more firmly against the abutting edge in the opening 19 in theclip through which the tongue extends. While any resulting movement ofthe two transverse members towards each other in this manner would, atmost, be only a very small fraction of an inch, nevertheless theexertion of this force is suflicient to accomplish the purpose ofsetting both transverse members into tighter engagement with therespective flange edges of the intervening main member 11, with theresult that the desired tight joint connection is established andmaintained. This is a very important feature of my invention and thistightening of the joint is also achieved with a minimum of labor. Thefact that the width of the notch 18 of the clip is made greater than thethickness of the center rib of the main member 11 makes possible anysuch self-adjustment of the two transverse members and connecting clipwith respect to the main member 11.

For supporting the ceiling grid structure and attaching the adjacentends of the various T-shaped members to the side walls of the room, Iprovide a wall strip 22 (Figures 1 and 2) adapted to be attached to eachwall W by nails or screws. a bottom horizontal flange 23 which isarranged to extend in the same horizontal plane as the bottom flanges ofthe members 11 and 12. The height of the wall strip 22 is made tocorrespond to the height of the center ribs of be members 11 and 12 andthe upper half of the wall strip is slightly offset outwardly from thewall.

An end clip 24 having two separate saddle portions 25 and 26 (Figure 1),is formed with a center right angle bend. One saddle portion 25 is setover the top of the wall strip 22 and the other saddle portion 26 is seton the center rib of the end of the T-shaped member which is to besecured to the wall. When the end clip 24 and the end of the T-shapedmember to be secured to the wall are in proper position, and thus withthe end of the flanged bottom of T-shaped member set against and flushwith the bottom flange 23 of the wall member 22, the saddle portion 26of the clip 24 is rigidly secured to the center rib of the T-shapedmember. This is done preferably by partially punching out two series ofopposed tongue-like The wall strip 22 is formed with I indentations 27and 28 (Figures 1 and 2), through the walls of the saddle portion 26 andthe interposed rib of the T-shaped member, similar to the partiallypunchedout indentations 20 and 21 previously described. This causes theend of the T-shaped member to be rigidly secured to the clip 24 and theclip 24 then serves to hold the end of the T-shaped member in place onthe wall member 22. Thus, the ends of all the T-shaped members of thegrid structure adjacent the wall surfaces are quickly and easilyattached to the wall member 22.

Since the clips 24, as well as the clips 17, are prefabricated, theclips 17 being provided with the openings 19, and since each transverseT-shaped member is also preformed with the pair of tongues 16, 16located near one end, the setting up of the grid, the securing of thesame in place, and the forming and tightening of each joint in the gridcan all be done with a minimum expenditure of time and labor.

Minor modifications would be possible in the grid structure which I haveillustrated and described without departing from the principle of myinvention, but when my invention is employed specifically in the formingof metal grids for acoustical ceilings and the like, which I believe tobe its most important use, I consider that the forming of the gridstructure in exactly the way I have described to be the preferred mannerof carrying out my invention.

I claim:

1. In a metal ceiling grid construction of the character describedcomprising parallel main members and aligned transverse members, saidmembers being of inverted T-shape with a vertical center rib and abottom horizontal flange and the bottom flanges of said main members andof said transverse members extending in the same horizontal plane, theimproved means for securing a pair of successive aligned transversemembers together supported on a main member therebetween with the endsof the bottom flanges of said pair of transverse members firmly thrustagainst the respective longitudinal edges of the bottom flange of saidmain member, said means consisting of an inverted U-shaped clip fittingover and joining the adjacent ends of the center ribs of said transversemembers, the top edge of the center rib of said main member having arectangular notch corresponding in width to the outside width of saidclip, said clip extending through said notch, the bottom edges of thewalls of said clip having a registering pair of notches centrallylocated on said clip, said center rib of said main member received insaid notches of said clip, the width of said notches in said walls ofsaid clip exceeding the thickness of said center rib of said mainmember, and thus enabling said clip to be slightly movablelongitudinally on said main member center rib, one end of said cliprigidly and permanently secured to the center rib of one of saidtransverse members, the walls of said clip near the other end of saidclip formed with two pairs of identical rectangular, transverselyaligned openings, the remote edges of said openings with respect to saidmain member being vertical, a pair of rectangular tongues on the centerrib of the other transverse member, the fold lines for said tonguesbeing vertical, said tongues being of approximately the same size assaid openings in said clip walls and in registration 6 t therewith, saidtongues extending toward said main member, and said tongues pressed intooutwardly-ofiset position through the openings in one of the walls ofsaid clip with as much as possible of each offset tongue parallel withsaid clip, the engagement of said tongues with said remote edges of theclip openings through which said tongues are pressed resulting in athrust of said transverse members against said main member.

2. A metal grid construction comprising parallel main members andaligned transverse members, said members being identical in crosssection and being of inverted T-shape with a center rib and a bottomflange, the bottom flanges of said main members and said transversemembers extending in the same plane, each pair of successive alignedtransverse members secured together and sup ported on an interposed mainmember by means of an inverted U-shaped clip fitting over and joiningthe adjacent ends of the center ribs of the transverse members in thepair, the top edge of the center rib of the interposed main memberhaving a rectangular notch corresponding in width to the outside widthof said clip, said clip extending through said notch, the bottom edgesof the walls of said clip having a registering pair of notches centrallylocated on said clip, said center rib of said main member received insaid notches of said clip, the width of said notches in said walls ofsaid clip exceeding the thickness of said center rib of the interposedmain member so as to enable said clip to be slightly movablelongitudinally on said main member center rib, one end of said cliprigidly and permanently secured to the center rib of one of thetransverse members of the pair, the walls of said clip near the otherend of said clip formed with two pairs of identical,transversely-aligned openings, the remote edges of said openings withrespect to the interposed main member being parallel to the center ribof the interposed main member, a pair of tongues on the center rib ofthe other transverse member of the pair, the fold lines for said tonguesbeing parallel to the center rib of the interposed main member, saidtongues being of approximately the same size and shape as said openingsin said clip walls and in registration therewith, said tongues extendingtoward the interposed main member, and said tongues pressed outwardlyinto offset position through the openings in one of the walls of saidclip with as much as possible of each offset tongue parallel with saidclip, the engagement of said tongues with said remote edges of the clipopenings through which said tongues are pressed resulting in an addedthrust of the pair of transverse members against the interposed mainmember.

References Cited in the file of this patent UNITED STATES PATENTS430,000 Clarke et a1. June 10, 1890 1,412,763 Buckingham Apr. 11, 19221,420,099 Hauser June 20, 1922 1,956,809 Robertson May 1, 1934 2,049,925Rafter Aug. 4, 1936 2,120,725 Zanin June 14, 1938 2,254,558 WilliamsSept. 2, 1941 2,351,127 Hodson June 13, 1944 2,710,679 Bibb et a1 June14, 1955

